Summary
This document proposes to supersede Airworthiness Directive (AD) 81-15-04 R1, which applies to certain The New Piper Aircraft, Inc. (Piper) Models PA-31, PA-31-300, PA-31-325, PA-31-350, and PA-31P-350 airplanes and currently requires repetitively inspecting for cracks at the elevator outboard hinge attachment on the horizontal stabilizer rear spar, and if cracks are found, incorporating a spar and hinge bracket assembly kit. The proposed action would require repetitively inspecting the horizontal rear spar in the area of the outboard hinge attachment and the outboard hinge attach bracket for cracks. When cracks are found or at a certain accumulation of time-in-service (TIS), the proposed AD would require modifying the horizontal stabilizer spar by incorporating an improved stabilizer spar and hinge bracket assembly kit that would terminate the repetitive inspections. The proposed AD is prompted by several field reports of cracks found during routine inspections on airplanes already in compliance with AD 81-15-04 R1. The actions specified by the proposed AD are intended to prevent failure of the horizontal stabilizer rear spar caused by cracks at the elevator outboard hinge attachment, which could result in loss of control of the airplane.